Good advice I got a few years back:
If you have to make a decision and there is no penalty for waiting, wait. More information may come.
If you have to make a decision now, or soon, then make it clean and mark it in your mind with the time and date that you made it. Better still, mark it in your business plan, with the key assumptions that drive the decision, so you can go back and review. Don’t blame yourself later for what you didn’t know when you had to decide.
Lots of good decisions have bad outcomes. That doesn’t make them bad decisions. The issue is what you knew when you had to decide. What assumptions you used.
If you made a decision before you had to, and it turned out later that you would have had more information if you’d waited, then think about penalties for waiting. Some decisions carry penalties, and some don’t.
For the opposite point of view, try Seth Godin’s I Need More Time.